2500A Round Copper Bus
2500A Round Copper Bus
(OP)
Hi all,
I have an outdoor metal-clad switchgear application at 34.5kV, 2500A that required the use of hollow round copper bus. Outdoor condition is hot and high humidity.
A 1/4 x 6' flat bar rated 2700 A @ 65 deg C rise was the guideline according to this Copper.org website. http://www.copper.org/applications/busbar/ampacity/busT1.htm
If I take the flat bar cross section and applied the equvalent cross section to the round copper bar, is it going to be valid? Say, a 2' diameter with 0.5' outer wall thickness?
Also, does heat shrinking the bus derate the temp rating hence the ampacity?
Any feedback will be very much appreciated.
Thanks in advance.
I have an outdoor metal-clad switchgear application at 34.5kV, 2500A that required the use of hollow round copper bus. Outdoor condition is hot and high humidity.
A 1/4 x 6' flat bar rated 2700 A @ 65 deg C rise was the guideline according to this Copper.org website. http://www.copper.org/applications/busbar/ampacity/busT1.htm
If I take the flat bar cross section and applied the equvalent cross section to the round copper bar, is it going to be valid? Say, a 2' diameter with 0.5' outer wall thickness?
Also, does heat shrinking the bus derate the temp rating hence the ampacity?
Any feedback will be very much appreciated.
Thanks in advance.






RE: 2500A Round Copper Bus
The rectangular bus should have the ampacity rating the same of higher than the tubular copper bus. It may be a good idea to adhere to industry standards for bus applications, e.g. IEEE Std 605:
http://standards.ieee.org/catalog/olis/subst.html
http://standards.ieee.org/reading/ieee/updates/errata/605-1998_errata.pdf
RE: 2500A Round Copper Bus
You should probably consult the copper supplier for specifics on the exact material being furnished.
RE: 2500A Round Copper Bus
http://www.hubbellpowersystems.com/powertest/catalog_sections/Technical_Data.pdf
RE: 2500A Round Copper Bus
RE: 2500A Round Copper Bus
I've posted this before, It's worth downloading and saving on disk. See table 13 on page 10..
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RE: 2500A Round Copper Bus
Try Google searching for "Hubbell Power Systems Anderson Electric"
It's the first hit I get, then go to catalogs, then refernece data. It's number 6 on the list.
RE: 2500A Round Copper Bus
RE: 2500A Round Copper Bus
More comment from current Fink, Beaty "Standard Handbook for Electrical Engineers":
Tubular conductors used on alternating current have a better current distribution than any other shape of conductor of similar cross-sectional area, but they also have a relatively small surface area for dissipating heat losses. These two factors must be balanced properly in the design of a tubular bus. Tubing provides a relatively large cross-sectional area in minimum space and has the maximum structural strength for equivalent cross-sectional area, permitting longer distances between supports. In outdoor substations, spans up to 40 or 50 ft with 6-in-diameter copper or aluminum tubes are considered practicable. ....
Current rating tables are included therein.